Opinion: Two (maybe three) big developments in Mueller's probe

A man who led the Trump campaign for part of 2016 surrendered himself Monday on charges that include conspiracy against the United States. And that was the relatively good news about the president's (former) men.

Paul Manafort and a former business associate, Richard Gates, are charged with failing to register or report income from their work as lobbyists for the government of Ukraine for more than a decade. But the indictment, released Monday, does not refer to Manafort's work during the summer of 2016 as campaign manager of Trump's presidential campaign. In fact, there's no indication -- in this indictment, anyway -- prosecutors have established that Manafort was part of an alleged collusion between the campaign and the Russian government.

UPDATE: Both Manafort and Gates pleaded not guilty in a court appearance Monday afternoon.

Unfortunately for Trump supporters, Manafort's indictment wasn't the only news to break from special counsel Robert Mueller's investigation into alleged collusion. Also Monday, Mueller's office announced a guilty plea on charges of lying to FBI agents by a man named George Papadopoulos, who served as a foreign-policy adviser to the campaign. Manafort is the bigger name, but Papadopoulos may prove to be the bigger story.

A plea document released Monday says Papadopoulos lied to investigators back in January about the timing and nature of his meetings and communications during 2016 with unnamed people overseas about a possible meeting between the Trump campaign and the Russian government, and about the existence of "thousands of emails" and "dirt" Moscow had about Trump's Democratic opponent, Hillary Clinton.

It's important here to note this: On its own, the Papadopoulos plea proves nothing about possible collusion. There's nothing in the document released Monday that indicates the campaign took what Papadopoulos was offering in the way of meetings with or "dirt" from the Russians. Most of the information in the document concerns what Papadopoulos learned from the foreigners -- a professor based in London he met in Italy, a Russian woman he met via the professor in London, and officials with the Russian Ministry of Foreign Affairs -- and passed along to higher-ranking officials in the campaign. The other campaign officials' responses are not generally included, although a footnote in the document observes that on one occasion his contact at the campaign forwarded his email to another campaign official, saying: "Let(')s discuss. We need someone to communicate that DT is not doing these trips. It should be someone low level in the campaign so as not to send any signal." (Not explained is exactly what kind of signal, and to whom, the campaign didn't want to send.)

That said, it's also important to note that a charge such as making false statements, and a defendant such as a relatively junior member of an organization under investigation, are a time-honored way for federal prosecutors to begin building or revealing their broader case in public. Papadopoulos was arrested back in July, and the document says that since then he has "met with the Government on numerous occasions to provide information and answer questions."

There could hardly be a clearer sign Papadopoulos' cooperation with investigators will probably lead to other charges against other people. What, and against whom, are the big questions.

In at least a couple of cases, the timing of some of these events is ... curious:

Papadopoulos met with federal agents for the first time "on or around Jan. 27, 2017." Now, Jan. 27 happens to be the day President Trump met with then-FBI Director James Comey for a one-on-one dinner at the White House. That night, Comey told Trump for the second time that he was not personally under investigation. It's also the night Trump told Comey he "need(ed) loyalty" and Comey demurred. Maybe there's a connection between the two events that day; maybe it's a coincidence.

On July 25, Manafort appeared before the Senate intelligence committee. On July 26, FBI agents raided Manafort's home in Alexandria, Va., at Mueller's behest. On July 27, Papadopoulos was arrested at Dulles International Airport outside Washington, D.C. Again: connection, or coincidence?

And now, because this story doesn't have enough twists and turns:

The Podesta Group earlier this year filed new disclosures about its work with a European think tank with ties to the same Ukrainian political party for whom Manafort worked. Last week, NBC News reported Mueller was also investigating the Podesta Group. Tony Podesta's brother, John, was chairman of Hillary Clinton's presidential campaign in 2016.

Add that to the news that the Clinton campaign and the Democratic National Committee helped pay the firm that produced the infamous dossier about Trump's activities in Russia, and it appears the range of possibilities here is quite wide. Perhaps no one colluded with the Russians. Perhaps the Trump campaign did; perhaps the Clinton campaign did. Perhaps the Russians played both sides for fools. Perhaps both campaigns were rotten from the head down, confirming many Americans' suspicions last year that the political system had produced a big, nasty mess.

Hint: Those last two possibilities are not mutually exclusive.

In any case, it seems clear the Mueller investigation is making progress and isn't nearly finished.